Since HUAWEI launched EMUI 5.0, it came with a feature called App Twin. App Twin allows user to run multiple instances simultaneously for one app, so user can set up multiple accounts for each instance, e.g. log-in multiple accounts for Facebook at same time. There are some applications that do this same function on the Play Store such “App Cloner” and “Parallel Space”, though I prefer using HUAWEI native feature to do the job.
Unfortunately App Twin only works on very few apps, like Whatsapp/Facebook or QQ/Wechat. But according to xda-developers forum, it can actually work with pretty much any application on your device even you don’t have root access. Here’s how it’s done (for device without root access)

Prerequisite:

Enable “Developer Options” and “USB Debugging” in “Setting” menu

Download Google latest android platform tool “adb”

Install HUAWEI latest driver “HiSuite”

A usb cable connect the device to PC

Find the “Package Name” for the apps you wish to enable App Twin, and the app has to be installed already (will explain later)

After installed HiSuite to your PC, connect the device and wait until the USB driver installed properly. Unzip android platform tool to your local folder, open up a command prompt, go to the unzipped folder, run adb shell as follow
Once you’re in an ADB shell, enter the following command to get current App Twin list:
I got output “null” because I don’t have any app using App Twin right now, so let’s add some apps to the App Twin list. The syntax for adding app to list will be like below:

To find the package name for your app, simply go to Google Play Store, search for the app you want, and look at the URL, you will find it like below:
Now let’s run adb command to put my existing app “Gmail” and “eBay” to the list:

When you want to add more apps to the list, remember be sure to APPEND the new app package name to the current list, and put the new list again, otherwise the existing apps with App Twin will be deleted from the list. For example, If I wish to add “Paypal” to my current list, I have to run:

For many old laser printers specially HPs, there is no dedicated driver for Windows 7. From HP website, I only could find the universal driver which I don’t like. Actually there are alternate print drivers we can use from Windows update, here is how:

Generally when you click the “Back” or “Forward” button on the browser, the page won’t refresh unless you tell the browser not saving the cache for it. To implement “Disable Browser Cache” for specific page in ASP.NET MVC 3, just simply use the “OutputCacheAttribute” from MVC 3 framework:

After I upgraded Ubuntu to 14.04 LTS, the HP LaserJet 1020 printer stopped working mysteriously, whatever print job sent to the print, it returns “job completed”, but has nothing to print out. I noticed the HPLIP driver has been used for the printer by default, but it didn’t work either even I changed the driver to foo2zjs via CUPS web interface.
After googled quite a while, I finally figured out that the foo2zjs package included in Ubuntu has some issues, as well as the HPLIP package. I decided to remove both of them out, and use the correct foo2zjs driver. See below for how:

Remove HPLIP package (if you had installed it manually, refer here for uninstall)

Shell

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sudo apt-getremove hplip

Get and install foo2zjs package from official site

Shell

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sudo apt-getinstall build-essential tix foomatic-filters groff dc

wget-Ofoo2zjs.tar.gzhttp://foo2zjs.rkkda.com/foo2zjs.tar.gz

tar zxf foo2zjs.tar.gz

cdfoo2zjs

make

sudo makeinstall

sudo makeinstall-hotplug

sudo makecups

Get HP LaserJet 1020 firmware files, and copy the files to system firmware folder. (use “1018” instead of “1020” for LaserJet 1018 printer)

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./getweb1020

sudo cpsihp1020.*/lib/firmware/hp/

Installing “foomatic-filters” may remove some CUPS packages, you can reinstall the CUPS or do it when you have problem in step 6